Results of review "somewhat reassuring," but more study needed.

Action Points

There was little risk of long-term cognitive decline related to cardiac procedures among elderly patients, according to a literature review, but the data were limited and better studies are needed to assess the risk.

Note that that given the paucity of high-quality studies examining long-term cognitive outcomes in elderly patients following heart procedures, clinicians should discuss the uncertainty about adverse cognitive outcomes with their older patients in pre-surgical counseling.

There was little risk of long-term cognitive decline related to cardiac procedures among elderly patients, according to a literature review, but the data were limited and better studies are needed to assess the risk, researchers said.

Based on independent rating of quality and strength of the evidence (SOE) of 17 randomized trials and four cohort studies, there was no difference in cognitive function among patients treated with on- and off-pump coronary artery bypass graft (CABG, six trials, low SOE), and no difference in function between patients treated with hypothermic and normothermic CABG (three trials, moderate to low SOE), reported Howard A. Fink, MD, MPH, of the Minneapolis Veterans Affairs Health Care System, and colleagues.

Overall, the analysis found little evidence of intermediate- or long-term cognitive impairment in patients age 65 or older following cardiac interventions, they authors reported in the Annals of Internal Medicine.

But the researchers cautioned that given the paucity of high-quality studies examining long-term cognitive outcomes in elderly patients following heart procedures, clinicians should discuss the uncertainty about adverse cognitive outcomes with their older patients in pre-surgical counseling.

"I think this analysis could be considered somewhat reassuring, but we need better studies comparing certain cardiac procedures in this population," Fink told MedPage Today. "There is still a great amount of uncertainty about the association between atrial fibrillation [catheter] ablation and cognition, for example, and whether there is a difference between transcatheter and surgical valve replacement."

Approximately 200,000 CABG surgeries, 50,000 carotid revascularizations, 50,000 cardiac valve replacements or repairs, and 10,000 catheter ablations for atrial fibrillation are performed annually in the U.S. among patients ages 65 and up, Fink and colleagues wrote.

While the potential impact of CABG procedures on cognitive decline has been extensively studied, it now appears that early studies overstated the link, the researchers noted.

"Later studies suggested that much cognitive impairment after CABG predated the procedure and was related to patient factors, such as age, education, and vascular disease," they wrote.

Studies of carotid revascularization and cognitive outcomes have also been mixed and the impact of cardiac valve procedures and catheter ablation on cognition is not well understood.

Fink said the long-term impact of cardiac procedures in older patients has not been well characterized because the vast majority of studies have included mostly middle-aged patients and have had short follow-ups.

The 17 randomized, controlled trials and 4 cohort studies included in the analysis were conducted between 1990 through 2014. The majority of patients (80%) were men, and the mean patient age was 68. One reviewer identified the studies included in the analysis, and two others independently rated the quality and SOE.

Two trials found no difference between surgical carotid revascularization and carotid stenting or angioplasty (low and insufficient SOE, respectively).

One cohort study found increased cognitive decline after transcatheter versus surgical aortic valve replacement, but this trial was found to have both selection and outcome measurement bases (insufficient SOE).

"The few eligible studies we identified reported little to no difference in cognitive outcomes between or within treatment groups, although conclusions were usually limited by scant and heterogeneous data and low individual study quality," the researchers wrote.

Fink said while "incident cognitive impairment" was used to measure cognitive outcome in many studies, there was no standardized definition of what this means.

The researchers concluded that future studies should include "a standardized definition of incident cognitive impairment that represents a clinically meaningful change."

"A consensus process that accumulating intervention data may help further define a cognitive battery that is sensitive to change over time, minimize learning effects, and will be broadly accepted and implemented," they wrote. "Long-term incidence of clinical outcomes, such as mild cognitive impairment and dementia, should also be reported."

Accessibility Statement

At MedPage Today, we are committed to ensuring that individuals with disabilities can access all of the content offered by MedPage Today through our website and other properties. If you are having trouble accessing www.medpagetoday.com, MedPageToday's mobile apps, please email legal@ziffdavis.com for assistance. Please put "ADA Inquiry" in the subject line of your email.